One new genus and two new species of oonopid spiders from Xishuangbanna Rainforest, southwestern China (Araneae, Oonopidae)

Abstract A new genus, Bannana, is established for two new species that resemble those of the Dysderoides complex. Two new species are described, Bannana crassispina sp. n. and Bannana parvula sp. n. Morphological descriptions and illustrations of both new species are given.


Introduction
The "Dysderoides complex", including the genera Dysderoides Fage, 1946, Himalayana Grismado, 2014and Trilacuna Tong & Li, 2007, was firstly proposed by Grismado et al. (2014). This Asian genera complex has a wide distribution, from Pakistan to Sumatra, and sharing the general morphology of the genitalia, chelicerae and labium.
When examining specimens collected from leaf litter in Xishuangbanna, Yunnan Province of China, two new species were recognized. They are very similar to those species of Dysderoides, having reduced eyes, deeply incised labium and complicated male palpal bulb, but without macrosetae on legs III and IV. Here a new genus belonging to the Dysderoides complex is established to accommodate these two new species.

Material and methods
Specimens in this study were mainly collected by pitfall-trapping and hand-collecting from leaf-litter in tropical rainforest in Xishuangbanna, Yunnan in 2006 and2007. All specimens are deposited in the Institute of Zoology, Chinese Academy of Sciences in Beijing (IZCAS).
The specimens were examined using a Leica M205C stereomicroscope. Details were studied with the use of an Olympus BX51 compound microscope. All illustrations were made using a drawing tube and inked on ink jet plotter paper. Vulvae were cleared in lactic acid. Photos were made with a Canon EOS 550D zoom digital camera (18 megapixels). Images from multiple focal planes were combined using Helicon Focus (version 3.10) image stacking software. Descriptions were generated with the aid of the Planetary Biodiversity Inventory descriptive goblin spider database and shortened where possible. Measurements were taken using an Olympus BX51 compound microscope and are in millimeters.
Etymology. The generic name is derived from the last a few letters of the type locality, 'Xishuangbanna', and is feminine in gender.
Diagnosis. The new genus is similar to Dysderoides but can be distinguished from the latter by the following combination of characters: 1) lacking macrosetae on legs III and IV; 2) having reticulate cuticle on the sternum and the sides of the carapace (Figs 1F, 3D, 4C, 5D), which is smooth in Dysderoides; 3) with radial furrows between coxae I-II, II-III, III-IV on the sternum, which is absent in Dysderoides; 4) females have large dorsal scutum (Figs 3A, B, 5E, F), which is absent or less than half of dorsum in Dysderoides. The new genus can be easily distinguished from Trilacuna and Himalayana by the reduced eyes (Figs 1F, 3D, 4C, 5D) and the reticulate cuticle on the sides of the carapace. Both Trilacuna and Himalayana have normal eyes and usually granulated or sometimes smooth on the sides of the carapace (Eichenberger 2011;Grismado et al. 2014;Li 2007, 2013). The new genus also can be distinguished from Trilacuna by the short postepigastric scutum in females (Figs 3G, 5G) and by having a furrow connecting the posterior tracheal spiracles in males (Figs 1G, 4F); can be distinguished from Himalayana by the absence of the acute projection in the prolateral dorsal part of the male bulb (see Grismado et al. 2014: fig. 62D-H) and the straight, stick-like sclerite in female genital area (Figs 2I, 6E). Description. Male: cephalothorax: carapace yellow, without any pattern, broadly oval in dorsal view, pars cephalica slightly elevated in lateral view, anteriorly narrowed to 0.49 times its maximum width or less, with rounded posterolateral corners, posterolateral edge without pits, posterior margin not bulging below posterior rim, anterolateral corners without extension or projections, posterolateral surface without spikes, surface of elevated portion of pars cephalica smooth, sides reticulated, thorax without depressions, fovea absent, without radiating rows of pits; lateral margin straight, smooth, rebordered, without denticles; marginal setae present. Clypeus margin unmodified, sinuous in front view, vertical in lateral view, median projection absent; setae light, needlelike. Chilum absent. Eyes absent (remnants still visible in B. crassispina sp. n.). Sternum: longer than wide, with radial furrows between coxae I-II, II-III, III-IV, uniform, not fused to carapace, median concavity absent, surface reticulated, microsculpture covering entire surface, anterior margin unmodified, posterior margin not extending posteriorly of coxae IV, anterior corner unmodified, distance between coxae approximately equal, lateral margins unmodified, without posterior hump; setae sparse, dark, needlelike, evenly scattered, without hair tufts (B. crassispina sp. n. has pairs of short setae in central part, as in Fig. 1C). Mouthparts: chelicerae straight, anterior face unmodified; without teeth on both promargin and retromargin; fangs without toothlike projections, directed medially, shape normal, without prominent basal process, tip unmodified; setae light, needlelike, evenly scattered; paturon inner margin with pairs of enlarged setae, distal region abruptly narrowed, posterior surface unmodified, promargin unmodified. Labium triangular, anterior margin deeply incised (as in Fig. 1C), same as sternum in sclerotization, not fused to sternum. Endites distally not excavated, anteromedian tip unmodified, posteromedian part unmodified, same as sternum in sclerotization. Abdomen: ovoid, rounded posteriorly. Dorsal scutum covering whole dorsum, strongly sclerotized, without color pattern. Epigastric scutum strongly sclerotized, surrounding pedicel. Postepigastric scutum strongly sclerotized, long, almost rectangular, covering nearly full length of abdomen length, anterior margin unmodified, without posteriorly directed lateral apodemes. Book lung covers large, smooth, anterolateral edge unmodified. Scutopedicel region unmodified, scutum not extending far dorsal of pedicel, plumose hairs absent. Posterior spiracles connected by groove. Spinneret scutum present, incomplete ring. Spinneret scutum without fringe of setae. Legs: pale, without color pattern; femur IV not thickened, same size as femora I-III, patella plus tibia I longer than carapace. Leg spines: tibiae I, II with 3 or 4 pairs of ventral spines each; metatarsi I, II with 2 pairs of ventral spines each, legs III and IV without spines. Genitalia: epigastric region with sperm pore large, oval, rebordered, situated in front of or at level of anterior spiracles. Palp normal size, not strongly sclerotized, right and left palps symmetrical, proximal segments yellow-brown; embolus light; trochanter normal size, unmodified; femur enlarged, attaching to patella basally; patella shorter than femur, not enlarged, setae unmodified; tibia not enlarged, distal part with modified setae in B. crassispina ( Fig. 2A, D); cymbium yellow-brown, narrow in dorsal view, not fused with bulb, not extending beyond distal tip of bulb; bulb 1.5 to 2 times as long as cymbium, tapering apically; distal part with several laminae that bear filiform projections surrounding the embolus.
Female: as in male except as noted. Palp without claw; spines absent. Abdomen: dorsal scutum large, covering more than 3/4 of dorsum (Figs 3A, 5E). Postepigastric scutum short, only around epigastric furrow, not fused to epigastric scutum (Figs 3G, 5G). Supraanal scutum absent. Postepigastric area setae needlelike. Genitalia: ventral view: without special external features; dorsal view: there are one transverse ventral plates, adjacent to a pair of short apodemes; posterior receptacle rounded to ovoid, extending anterior by a narrow, stick-like sclerite (Figs 2H, I, 6D Etymology. The specific name is Latin, "crass-" = thick, and "spin-" = seta, referring to the thick bristles on male palpal tibiae. Diagnosis. The males of the new species can be distinguished from B. parvula sp. n. by the thick bristles on palpal tibiae (thb in Fig. 2A, D) and rows of setae on the central part of sternum (Fig. 1C); females of the new species are similar to those of Dysderoides synrang Grismado & Deeleman, 2014, but can be distinguished by the absence of macrosetae on legs III and IV, and by the large dorsal abdominal scutum.